DAC: Before I jump in...

I've an older but pleasing to my ears system (Acoustat, ARC) and recently I've dabbled with digital by buying, and enjoying, a Bluesound Node2i. I'm starting to look at a separate DAC. The 2i sounds pretty nice via it's internal DAC but I'd like to improve things in a thoughtful, and reasonable, manner i.e. I'm not going to spend way more on a DAC than my other components. As a means of comparison, I have an ARC SP8 MkII and ARC VS110. My question is has technology progressed such that buying a newer though lower class DAC would be superior than an older DAC like an ARC DAC2? Would something from Schiit or Jolida, for instance, sound better. I'm looking for some general, constructive thoughts on the matter really to help guide my search.
Thank you and happy listening!